The National Library of Medicine (NLM) provides many articles in free, full-text form in order to disseminate health information.
Please view the Powerpoint for further instructions on using the NLM Databases.
PMC is a digital archive of life sciences journal literature that includes more than two million articles. Each article is available free and full text.
While there are 270 different databases available through NLM (complete list here), not every database will be helpful for Hazmat personnel.
One way to whittle down the databases to a usable number is to narrow the subject terms to "Disasters," "Disaster Medicine," and "Toxicology." This leaves you with 30 databases.